CVE-2019-19977CriticalCVSS 9.8
libESMTP through 1.0.6 mishandles domain copying into a fixed-size buffer in ntlm_build_type_2 in ntlm/ntlmstruct.c as demonstrated by a stack-based buffer over-read.
🔗 CVE IDs covered (1)
📋 Description
Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability? One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
🎯 Affected products2
- azl3 libesmtp 1.0.6-21 on Azure Linux 3.0
- cbl2 libesmtp 1.0.6-21 on CBL Mariner 2.0
✅ Remediation
KBCBL-Mariner Releases (Security Update) — fixed build 1.0.6-21